<!doctype html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Document</title>
    <style>
        *{padding:0;margin:0;}
        .box{
            width: 800px;
            margin:100px auto;
        }
        input{
            width: 500px;
            padding-left:10px;
            height: 50px;
            font:16px/50px microsoft yahei;
            color:#666;
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        li{
            list-style:none;
            height: 50px;
            width: 500px;
            padding-left:10px;
            background-color:darkred;
            color:#fff;
            font-size:20px;
            margin-top:10px;
            line-height:50px;

        }
    </style>
</head>
<body>
<div class="box">
    <input type="text">
    <ul></ul>
</div>

<script>
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    var oUl=document.getElementsByTagName("ul")[0];
    document.onkeyup=function(ev){
        ev=ev||event;
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</script>
</body>
</html>